Sulphonic acid of the benzene series



Patented Apr. 23, 1935,

SULPHQNIC ACID THE BENZENE SERIES 7 Richard Stiisser, Cologne-Deutz-on-the Rhine, Germany, assignor to General Aniline Works, Inc., New York, N. Y., a corporation of Delaware No Drawing. Application December: 10, 1932, Serial No. 646,720. In Germany December 14,

V '5 claims. (01. 260-124) a crystallized form. The 5-chloro-2- amino-lnethoxybenzene-4-sulphonic acidof the formula OCH;

The'present invention'relate's to new sulphonic acids of the benzene series, more particularly it relates to compoundswhich may be represented by the probable general formula is filtered with suction, washed with water and dried; The new sulphonic acids forms well crystallizing alkali metals which can be recrystallized from water.

The zene--sulphonic acid prepared in an analogous manner is more easily soluble in water, the 1- -methoxy-Z-benzoylamind-5-chloro-benzene 4 2 My newsulphonic acids of the benzene series are obtainable by sulphonating a benzene compound of the general formula substances, difficultly toeasily soluble inwater, forming well erystalizing watersoluble alkali metal salts, and being valuable intermediate products in the manufactureo'f dyestuffs.

The following examples-serve to illustrate my invention, without limiting'it thereto:

Example 1. 100 grams of 5-chloro -2-amino-lmethoxybenzene are stirred inSOO grams of sulphuric acid monohydrate at, a temperature between 40 and 50 C. until from a test portion which has been diluted with water 5-chlorc-2- amino-lamethoxybenzene is no. more precipitated by the addition of aqueous caustic soda. i-The sulphonation mixture is then poured onto ice whereby the sulphonic acid formed; separates My new sulphonic acids are generallycolorless sulphonic acid is more difi'icultly soluble in water.

Example 2.--l grams of -chloro-2-acetoacetylamino-l-methoxybenzene are introduced gradually with stirring into 400 grams of a sulphuricacid containing 20% of S03 at a temperature of C. When the S-chIorO-Z aceto-acetyI amino-l-methoxybenzene has been dissolved, the 1 soda is scarcely soluble in cold water and iorms alkali metal salts which are difiicultly soluble in water and can be recrystallized from the same.

Example 3.--100 gramsof 5,-chloro-2-acetoacetylamino-l-ethoxybenzene are introduced while stirring into 400 gramsof sulphuric acid containing of $03 at a temperature of 20 C.

After all has been.intro duced, the mass is heated for some time at C. until all has dissolved and a test portion yields a clear solution when adding an aqueous soda solution. When the sulphonation is complete, the reaction mixture is cooled down to zero, and the working up is performed as des ribed in Example 1. The 5-chloro-2;'aceto- 1-methoxy-2-acetylamino-5-chloro-benacetylaminol-ethoxybenzene-e-sulphonic of the formula acid SOzH

is difficultly soluble in cold water; it forms well crystallizing alkali metal salts which can be recrystallized iroin water; With diazo compounds it couples with the formation of azo dyestuffs.

ExampZe 4.-l00 grains of 5-chloro-2-benzoyl acetylamino-l-methoxybenzene are introduced while stirring into 500 grams of sulphuric acid containing 20% of S03 and stirred for some time at a temperature of 25 C. until a test portion yields a clear solution in diluted aqueous soda solution. The working up is performed as described in Example 1. The new sulphonic acid of the formula O-GHI H N/ H 01 o o-om-ooGo 0-OHr-C 0- SO|H O1 is soluble in hot water and in dilute aqueous alkalies. It couples with diazo compounds with the formation of azo dyestuffs.

The compound of the formula prepared in an analogous manner is somewhat more easily soluble in water and dilute aqueous alkalies. I

I claim: 1, The compounds of the general formula Pl N wherein alk stands for an alkyl group, X stands for hydrogen or an acyl group and n stands for one of the numbers one or two in such a manner that n can be two only in case X stands for acyl, being generally colorless substances, difiicultly to easily soluble in water, forming well crystallizing alkali metal salts, and being valuable intermediate products in the manufacture of dyestuffs.

2. The compounds of the general formula wherein alk stands for an alkyl group, X stands for hydrogen or an acyl group, being generally colorless substances, difiicultly to easily soluble in water, forming well 'cryst'allizing alkali metal salts and being valuable intermediate products inthe manufacture of dyestuffs I 3. The compounds of the general formula OzH wherein alk stands for an alkyl group, and R stands for a hydrocarbon radicle of the alkyl or benzene series, being generally colorless sub,- stances, diflicultly to easily soluble in water, forming well crystallizing alkali metal salts, and being valuable intermediate products in the manufac- V ture of dyestuffs 4. The compound of the formula being scarcely soluble in cold water, forming a well crystallizing alkali metal salt and being a valuable intermediate product in the'manufacture of dyestuffs.

5. The compound of the formula. being difficultly soluble in cold. water, forming a. 04km well crystallizing alkali metal salt and being a H valuable intermediate product in the manufacture of dyestufls.

\OWOHPOOOH' RICHARD s'rUssER. 5 

